class_docstr: Test that a device different to default.qubit gives the same result
docstr: Test that arbitrary multi-mode Projector expectation values are correct
docstr_tok: ["Test","that","arbitrary","multi-mode","Projector","expectation","values","are","correct"]
code: def test_projector_expectation(self, device, state, tol, benchmark):
      """Test that arbitrary multi-mode Projector expectation values are correct"""
      n_wires = 2
      dev = device(n_wires)
      dev_def = qml.device("default.qubit", wires=n_wires)
  
      if dev.shots is not None:
          pytest.skip("Device is in non-analytical mode.")
  
      if "Projector" not in dev.observables:
          pytest.skip(
              "Device does not support the Projector observable."
          )
  
      if dev.name == dev_def.name:
          pytest.skip("Device is default.qubit.")
  
      theta = 0.432
      phi = 0.123
  
      def circuit(theta, phi, state):
          qml.RX(theta, wires=[0])
          qml.RX(phi, wires=[1])
          qml.CNOT(wires=[0, 1])
          return qml.expval(qml.Projector(state, wires=[0, 1]))
  
      qnode_def = qml.QNode(circuit, dev_def)
      qnode = qml.QNode(circuit, dev)
  
      grad_def = qml.grad(qnode_def, argnum=[0, 1])
      grad = qml.grad(qnode, argnum=[0, 1])
  
      def workload():
          return (
              qnode(theta, phi, state),
              qnode_def(theta, phi, state),
              grad(theta, phi, state),
              grad_def(theta, phi, state),
          )
  
      qnode_res, qnode_def_res, grad_res, grad_def_res = benchmark(
          workload
      )
  
      assert np.allclose(qnode_res, qnode_def_res, atol=tol(dev.shots))
      assert np.allclose(grad_res, grad_def_res, atol=tol(dev.shots))
  
file_path: pennylane/pennylane/devices/tests/test_compare_default_qubit.py
imports: import pytest
  from flaky import flaky
  import pennylane
  from pennylane import numpy
  from pennylane.templates.layers import RandomLayers
label_desc: Use image node_id 2 for calling the TestComparison obj's underlying member method code with example usage: obj.test_projector_expectation(device, state, tol, benchmark) and returns: qml, qnode,  qnode_def,  grad,  grad_def